Fuel Injection Valve

Patent metadata

Field	Value
Publication number	US-2019249631-A1
Application number	US-201716316922-A
Country	US
Kind code	A1
Filing date	Jul 12, 2017
Priority date	Aug 26, 2016
Publication date	Aug 15, 2019
Grant date	—

Abstract

Provided is a fuel injection valve capable of stroking a valve body in large and small two stages and capable of precisely controlling an injection flow rate at the stroke. Therefore, the fuel injection valve of the present invention is provided with a valve body for opening or closing a flow path, a movable element for driving the valve body in a valve opening direction, and a magnetic core for attracting the movable element, in which the movable element is separately configured from the valve body, and is configured by a first movable element having a first facing surface facing the magnetic core and having the first facing surface attracted by the magnetic core, and a second movable element separately configured from the first movable element, having a second facing surface facing the magnetic core, and having the second facing surface attracted by the magnetic core.

First claim

1 . A fuel injection valve comprising:
a valve body configured to open or close a flow path; a movable element configured to drive the valve body in a valve opening direction; and a magnetic core configured to attract the movable element, wherein the movable element is separately configured from the valve body, and is configured by a first movable element having a first facing surface facing the magnetic core and having the first facing surface attracted by the magnetic core, and a second movable element separately configured from the first movable element, having a second facing surface facing the magnetic core, and having the second facing surface attracted by the magnetic core.

2 . The fuel injection valve according to claim 1 , wherein
the second movable element moves the valve body to an upstream side in a case where the second movable element moves toward the magnetic core, and the first movable element moves the valve body to the upstream side in a case where the first movable element moves toward the magnetic core.

3 . The fuel injection valve according to claim 1 , wherein
the second facing surface of the second movable element is arranged on an outer diameter side with respect to the first facing surface of the first movable element.

4 . The fuel injection valve according to claim 1 , further comprising:
a coil configured to cause a magnetic attraction force between the magnetic core and the movable element when a drive current flows, wherein the second facing surface of the second movable element is attracted to come into contact with the magnetic core in a case where a set first drive current flows in the coil.

5 . The fuel injection valve according to claim 1 , further comprising:
a coil configured to cause a magnetic attraction force between the magnetic core and the movable element when a drive current flows, wherein only the second facing surface of the second movable element is attracted to come into contact with the magnetic core in a case where a set first drive current flows in the coil.

6 . The fuel injection valve according to claim 1 , further comprising:
a coil configured to cause a magnetic attraction force between the magnetic core and the movable element when a drive current flows, wherein the second facing surface of the second movable element is attracted to come into contact in a case where a set first drive current flows in the coil, and the first facing surface of the first movable element and the second facing surface of the second movable element are attracted to come into contact in a case where a second drive current larger than the first drive current flows in the coil.

7 . The fuel injection valve according to claim 1 , further comprising:
a coil configured to cause a magnetic attraction force between the magnetic core and the movable element when a drive current flows, wherein only the second facing surface of the second movable element is attracted to come into contact with the magnetic core in a case where a set first drive current flows in the coil, and the first facing surface of the first movable element and the second facing surface of the second movable element are attracted to come into contact with the magnetic core in a case where a second drive current larger than the first drive current flows in the coil.

8 . The fuel injection valve according to claim 1 , wherein
a first clearance between the first facing surface of the first movable element and the magnetic core is configured to be larger than a second clearance between the second facing surface of the second movable element and the magnetic core in a valve closed state.

9 . The fuel injection valve according to claim 1 , wherein
an outer peripheral portion of the first movable element is configured to face an inner peripheral portion of the second movable element in a direction orthogonal to a valve body axial direction, and a downstream-side end surface of the first movable element is configured to face an upstream-side end surface of the second movable element in the valve body axial direction.

10 . The fuel injection valve according to claim 1 , wherein
a recessed portion recessed toward a downstream side is formed on an inner diameter side in the second movable element, and the first movable element is arranged inside the recessed portion.

11 . The fuel injection valve according to claim 1 , wherein
an axial maximum length of the second movable element is configured to be longer than an axial maximum length of the first movable element.

12 . The fuel injection valve according to claim 1 , wherein
the valve body has a protruding portion protruding toward an outer diameter side on an upstream side, and a downstream-side end surface of the first movable element faces and is supported by an upstream-side end surface of the protruding portion.

13 . The fuel injection valve according to claim 1 , wherein
the valve body has a valve body engaging portion engaged with the first movable element on an upstream side, and the first movable element is engaged with the valve body engaging portion to move the valve body to the upstream side in a case where the first movable element moves to the upstream side.

14 . The fuel injection valve according to claim 1 , wherein
the valve body has a valve body engaging portion engaged with the first movable element on an upstream side, and the first movable element has a first engaging portion engaged with the second movable element, and when the second movable element and the first movable element are engaged with each other by the first engaging portion in a case where the second movable element moves to the upstream side, the first movable element and the valve body engaging portion are engaged with each other, to move the valve body to the upstream side.

15 . The fuel injection valve according to claim 1 , further comprising:
a first spring configured to bias the valve body to a downstream side.

16 . The fuel injection valve according to claim 1 , further comprising:
a second spring attached to the valve body, and for biasing the first movable element to a downstream side.

17 . The fuel injection valve according to claim 15 , further comprising:
a third spring configured to bias the second movable element to an upstream side.

18 . The fuel injection valve according to claim 16 , wherein
a biasing force of the first spring is set to be larger than a biasing force of the second spring.

19 . The fuel injection valve according to claim 17 , wherein
a biasing force of the first spring is set to be larger than a biasing force of the second spring, and the biasing force of the second spring is set to be larger than a biasing force of the third spring.

20 . The fuel injection valve according to claim 1 , wherein
an outer diameter of an outer peripheral portion in an upstream-side end surface of the first movable element is configured to be larger than an inner diameter of an inner peripheral portion on a downstream-side end surface of the magnetic core.

Assignees

• Hitachi Automotive Systems Ltd

Inventors

• Miyamoto Akiyasu
• Ogura Kiyotaka
• Hohkita Atsushi
• Ishizuka Yuto
• Miyake Takao

Classifications

• F02M61/10

  Other injectors with elongated valve bodies, i.e. of needle-valve type · CPC title

• F02D41/20

  Output circuits, e.g. for controlling currents in command coils · CPC title

• F02M61/20

  Closing valves mechanically, e.g. arrangements of springs or weights {or permanent magnets; Damping of valve lift} · CPC title

• F02M51/0657 Primary

  the body being hollow and its interior communicating with the fuel flow · CPC title

• B05B1/3053

  the actuating means being a solenoid · CPC title